Lightning is perhaps the most misunderstood, most unpredictable, and most dangerous meteorological phenomena. The average lightning bolt is over one million volts, over 30,000 amps, and is nearly 55,000 degrees Fahrenheit (hotter than the surface of the sun). This destructive power is responsible for over 10,000 deaths around the world (about 60 across the United States), annually. Additionally, lightning is responsible for roughly 60 percent of all wildfires. Although all thunderstorms produce lightning, lightning can actually occur without a thunderstorm. Given the destructive nature and unpredictability of lightning, accurately detecting lightning is even more critical.
Conventional lightning detection systems are fairly large and expensive and primarily capture the electromagnetic field signature of a lightning strike. These conventional systems fall into three categories: ground-based, mobile, and satellite-based. FIG. 1 is an illustration of the three primary types of conventional lightning detection systems. Because of the electromagnetic and electrostatic activity occurring during a thunderstorm, conventional detectors will have a ratio of successful detection much lower than 100%.
Ground-based systems, such as the Vaisala™ sensor 100 of FIG. 1, include a network of antennas to sense lightning flashes and radiofrequency (RF) energy. They triangulate data from multiple sensors to determine distance and location. Data from these systems is often correlated with weather radar data. The National Weather Service, for example, uses ground-based detection systems. Ground-based systems, however, are limited in the types of lightning they can accurately detect. They are also costly and not available to individual subscribers, or to the general public.
Single-point (e.g., mobile or portable) detection systems include a single omni-directional antenna and measure range and location (e.g., azimuth) based on signal frequency and attenuation. These systems can detect the approach of a lightning system, but don't do as well pinpointing location. They also suffer from high false alarm rates. Single-point systems, however, are less costly, and are available to individual sub scribers.
More advanced single-point systems, such as the Mtech™ system 102, are used to detect thunderstorms at airports and other areas where safety is a factor. These more advanced systems provide detection using long-range lightning sensors that allow monitoring of lightning strikes and thunderstorm cell development. The system 102, of FIG. 1, correlates the electric and magnetic signatures of lightning strikes to provide range and azimuth information.
Satellite-based detection systems, such as the system 104, include a network of satellites to detect data related to location, time, and amplitude of lightning strikes with high levels of accuracy. Satellite-based systems, however, are also not available to individual subscribers. Additionally, the time delay created by the distance of the network to the lightning strike can make satellite-based lightning detection systems impractical for detecting lightning strikes in real-time.